The invention relates to an aerodynamic body and to a high-lift system comprising such an aerodynamic body.
U.S. Pat. No. 3,005,496 describes a helicopter rotor blade adjustably mounted for pitch angle control comprising a compressed air duct in which a valve closure member is rotatably disposed. At the blade tip a series of passages which can be opened and closed by the valve closure member, which open as ports from the hollow blade spar and which lead to a slot near the trailing edge of the blade. With this arrangement, any changes in the rotor blade pitch angles during the rotation thereof, will produce relative pivotal movement between the blade and the vane arm and hence, a turning of the jet ports relative to the valve closure member.
Airfoils with an inner channel which opens as ports are also disclosed in U.S. Pat. No. 3,692,259 and U.S. Pat. No. 6,390,116 B1.
U.S. Pat. No. 5,772,156 A describes the removal by suction of air through an inlet at the top of a wing, and to the blowing out through an outlet at the bottom of the wing, which outlet is connected to the inlet by way of a duct. A compressor is used to drive the airflow.
From U.S. Pat. No. 5,366,177 A removal by suction of air from a perforated exterior skin area at the top of a lift flap for influencing the boundary layer is known. Furthermore, according to this document a suction generating device comprising a pump, a turbo compressor or an electrically or hydraulically operated vacuum system is provided.
In the NASA study “Study of the Application of Separation Control by Unsteady Excitation to Civil Transport Aircraft” by J. D. McLean et al. of June 1999 and in the study “Designing Actuators for Active Separation Control Experiments on High-Lift Configurations” by Ralf Petz and Wofgang Nitsche, Berling University of Technology the option of pulsed blowing-out of air on the outside of a wing is described.